Lego Technic® Heavy Duty Truck

This is a heavy-duty tow truck pulling another truck. Heavy duty means it is used to pull BIG trucks.  It  is similar to the Lego truck, except this truck has an extra axle and set of wheels just behind the front doors.  In this exercise, you will explore how the Lego Truck works. Read about the tow truck in the panels below. Then do the numbered steps. All questions must be answered in complete sentences. If working in a group, all members must contribute, but one set of answers may be handed in in one student's notebook. The names of all students working on the project must be included each day.

In this picture, you can see a heavy-duty tow truck picking up a tractor-trailer after a wreck. Once the truck is on its wheels, then the tow truck will lift up the front of the truck using the lift bar and tow the truck to repair shop (after the stuff in the back up the truck is transferred to another truck).

This link talks about the different parts of a heavy-duty tow truck.

Play with the truck. Enjoy it. It's how we learn. But we have to put a limit on it.

Life the hood of the truck as shown in the picture.  The things with red axles and gray round things represent the pistons. In real trucks and cars, the pistons covered by cylinder heads so you don't get to see them. What happens when move the truck backwards and forwards? What do you think this is trying to show?

On the driver's side, there are two gears. Turn the gears and describe what happens. What happens when you turn the front gear. Why is would you want wheels to go up and down? Turn the back gear. What happens when you turn that gear? What would that be important?

In the picture, you can see there is a little black lever just behind the driver in the orange area right in front of the outrigger. It is surrounded by gray plastic. Above the lever, there is a black pump thing which is an air pump (like a small basketball or football (soccer ball) pump). Pump that a few times and move the lever up an down. Describe what happens to the underlift. 

Hydraulics are when there is a liquid like water or oil inside a closed space. This video explains them. You will answer the question: What are hydraulics? Why are they so helpful? This truck actually uses air instead of oil or water, but the principal is exactly the same thing. Air is easier to use because it is cleaner (no water or oil to clean up). The pictures on the left (below the video link) show some of the details of air pump, levers and tubing. 

There are two levers on the left. Pump the pump and move the levers. What do they do?

Turn the gears on the left (one is being turned by the kid in the photo), and other is just behind it above the wheel. What do the gears do? 

There are two pulleys in back near the underlift. What are they for?

On the top of the can where the driver would sit, right in the middle, there is a gear you can turn. What happens when you turn the gear?